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I have spent many hours reading about HICAS this morning, and finally understand what it actually is and what it can do. I only plan on street driving, and definately wouldnt be looking at using my car seriously at the track for a few years. My thought is to keep HICAS for the time-being when my car (car to be...) R33 GTS will just be a daily driver/street car. Would you guys agree???

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I have spent many hours reading about HICAS this morning, and finally understand what it actually is and what it can do. I only plan on street driving, and definately wouldnt be looking at using my car seriously at the track for a few years. My thought is to keep HICAS for the time-being when my car (car to be...) R33 GTS will just be a daily driver/street car. Would you guys agree???

Definently agree.

For street use, and even some 'spirited' driving through some nice twisty corners, the HICAS is actually quite good. It allows the car to remain slightly better balanced through the corners. The problems occur as soon as the rear end has let go (i.e. for drifting, etc), when it leaves you with a kinda 'sloppy' feeling.

The first time you feel the HICAS kick in at high speeds (it only kicks in after about 70km/h iirc) it can feel quite unnerving... almost like understeer but not at the same time! Once you're used to it, it's okay. For "grip racing", its really quite good... but for anything where you want to maintain control over the rear end without the computer trying to "help" you, it's gotta go.

also removing hicas will make your car feel heavier when parking etc...

with 18" rims, 320mm steering wheel and hicas removed mine is like an anvil... but you get used to it pretty quick...

also removing hicas will make your car feel heavier when parking etc...

with 18" rims, 320mm steering wheel and hicas removed mine is like an anvil... but you get used to it pretty quick...

Really? It really shouldn't make any difference whatsoever. The HICAS is designed to only kick in at higher speeds (i.e. 70km/h+ iirc), and doesn't move under that (unless you're parking at some serious speeds! :thumbsup:)

The 4WS system on the Honda's is designed as a parking aide, as it actually works in the direct oppposite way to that of a 'line. Ours turns the rear wheels THE SAME WAY as the front wheels... the hondas turn the opposite (tighter turning circle). With ours the car kinda 'side-steps' across the road slightly rather than having to turn and lean the car over.

Edited by Samon
Really? It really shouldn't make any difference whatsoever. The HICAS is designed to only kick in at higher speeds (i.e. 70km/h+ iirc), and doesn't move under that (unless you're parking at some serious speeds! :thumbsup:)

The 4WS system on the Honda's is designed as a parking aide, as it actually works in the direct oppposite way to that of a 'line. Ours turns the rear wheels THE SAME WAY as the front wheels... the hondas turn the opposite (tighter turning circle). With ours the car kinda 'side-steps' across the road slightly rather than having to turn and lean the car over.

Can you explain why my car steered like a forklift when going around a roundabout when hicas was still fitted and working. And no i wasn't going anywhere over 30ks round the roundabout.

Really? It really shouldn't make any difference whatsoever. The HICAS is designed to only kick in at higher speeds (i.e. 70km/h+ iirc), and doesn't move under that (unless you're parking at some serious speeds! :P )

The 4WS system on the Honda's is designed as a parking aide, as it actually works in the direct oppposite way to that of a 'line. Ours turns the rear wheels THE SAME WAY as the front wheels... the hondas turn the opposite (tighter turning circle). With ours the car kinda 'side-steps' across the road slightly rather than having to turn and lean the car over.

Pretty sure they turn the opposite way to the fronts to go the same direction as they are in the other end of the car. If they turned the same way it would make the car very scary to drive, by making it slide more. The tyres would be on a greater angle away from the direction of travel. As the car goes around the corner they turn the opposite way to make the tyres point in the direction the back end wants to slide in, therefore keeping more traction. I hope my explenation is understandable, it makes sense in my head.....

Pretty sure they turn the opposite way to the fronts to go the same direction as they are in the other end of the car. If they turned the same way it would make the car very scary to drive, by making it slide more. The tyres would be on a greater angle away from the direction of travel. As the car goes around the corner they turn the opposite way to make the tyres point in the direction the back end wants to slide in, therefore keeping more traction. I hope my explenation is understandable, it makes sense in my head.....

It does different things depending on the speed you're traveling...

Performance%20Tuning%20Systems%20HICAS%20explanation.jpg

As you can see from that diagram (from Nissan USA)...

Low speeds: HICAS does nothing... disabled

Medium speeds: rears turn the opposite way to the fronts at first (i.e. tighter turning angle), then once the HICAS computer detects that the car is responding to the turning, the rears turn back the opposite way, slightly reducing the turning circle but improving stability (i.e. theoretically less body-roll because it is kinda 'crab-walking' across the road rather than rotating around a center axis).

High speeds: rears turn the same direction as the fronts, like the second stage of the medium speed above.

I'm not sure of the official values for low, medium or high speeds though.

why the hell does it make the car heavier at low speeds then?

Hmmm... I dunno! It may depend on what they class as "low speed" and what you class as "low speed". i.e. if it's actually classified as "medium speed" then yeah, without it it's gonna feel a lot heavier... I'd love to throw my car up on a hoist and play around with the steering at different 'speeds' to see what happens...

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